Improvement in tubes and flues for steam-boilers



UNITED STATES' |ELMFENT OFFICE.

JOSEPH H. WILKINSON, OP SOUTH NEWMARKET, NEW HAMPSHIRE.

IMPROVEMENT IN TUBES AND FLUES FOR STEAM-BOILERS.

Specification forming part of Letters Patent No. 154,203, dated August 18, 1874; application filed August 10, 1874.

To all whom it may concern:

Be it known that I, JOSEPH H. WILKIN- SON, of South Newmarket, in the county of .Rockingham and State of New Hampshire,

of the invention, such as will enable others Skilled in the art to whichit pertains to make and use it, reference being had to the accompanying drawings, which form part of this specification.

This invention consists in the insertion into the tubes or flues of tubular steam-boilers of a central core provided with blades or vanes, so arranged as shall cause the products of combustion when passing through the tubes to impinge on all the internal surface of the same, as will hereafter be explained.

The accompanying drawings represent my invention.

To explain the nature, purpose, and utility of my invention, I will briefly describe the construction and operation thereof, and the manner of preventing the enormous waste of heat attendant on the use of horizontal steam boilers as commonly manufactured.

Where the products of combustion rare alp lowed to escape lfreely from the tubes they will always be found to be several hundred degrees above the temperature of the steam in the boiler, thus showing that an enormous waste of heat is taking place, and that the products in passing through do not impinge on the whole surface of the tubes, but a very small part of it. Furthermore, the heated gases, almost as soon as they enter the tubes, forsake the lower surface and rise to the upper surface, and then are passed through the tubes with a greatly-increasing velocity, the velocity increasing as the farthest end of the tube is reached. The external upper surface being that portion on which incrustation of saline and other sedimentary matter makes a lodgment, 'so that the heated products of combustion fail to yield up their heat to the tube and its surrounding water; also that the upper surfaces of the tubes become burned by the intense'heat upon that portion, and thus become a fertile source of trouble and expense.

To remedy the foregoing evils, and effect an economical use of fuel, I make no new construction of boilerfor my device can be applied to any tubular boiler now in usebut I construct a central core, B, for insertion in the tube A, Said core being provided with any desired number of blades or vanes, C, running parallel with each other, and at equal distances apart, the blades and core being of sufficient diameter to fill the bore of the tube.

It will thus be seen that the tube, when the core is inserted, is converted into a number of separate and distinct passage ways, so that whatever volume of the heated products of combustion enters any given passage-way it is compelled to remain in the same until the exit end of the tube is reached, and, as the draft acts with equal force on all the passage-ways, a uniform impingement of the heated products of combustion is effected on all the internal surfaces of the tube or tubes.

Another advantage of the core and blades is, that their upper surf'ace forms a l.odg ment, in a great degree, for dead sparks and other foreign matter, which would otherwise fall and rest on the lower internal surface of the ue, and thus prevent the heated products of combustion from giving up their heat to that portion of the tube.

It will also be noticed that my core is not made to extend to the full length of the tube. My reason for this is, that I nd it best to allow the entrance end of the tube its full area for the products of combustion to enter, as it then becomes a kind of reservoir for the heated gases, from which the series of passage-ways receive their supply.

Again, it will be seen that I make my core preferably with an increasing diameter; for as the heated gases give up their heat to the tubes their volume will be diminished; therefore, to secure a continuous pressure of the heated gases on the tube,`I increase the diamf eter of the core.

Having now described my invention, what I claim as my invention, and desire to secure In testimony that I claim the foregoing I by Letters Patent, ishave hereunto set my hand this 8th day of The combination, With the tubes or flues August, 1874. i

of a tubular or ue boiler, of a central core, JOS. H. WILKINSON.

provided with a series of blades or vanes, sub- Witnesses:

stantially as and for the purposes set forth FRANK GLAUDY,

and described. F. A. LEHMANN. 

